@article {jopjauto07, title = {Autonomic resource provisioning for software business processes}, journal = {Information and Software Technology}, volume = {49}, year = {2007}, month = {January}, pages = {65-80}, abstract = {Software development nowadays involves several levels of abstraction: starting from the programming of single objects, to their combination into components, to their publication as services and the overall architecture linking elements at each level. As a result, software engineering is dealing with a wider range of artifacts and concepts (i.e., in the context of this paper: services and business processes) than ever before. In this paper we explore the importance of having an adequate engine for executing business processes written as compositions of Web services. The paper shows that, independently of the composition language used, the overall scalability of the system is determined by how the run-time engine treats the process execution. This is particularly relevant at the service level because publishing a process through a Web service interface makes it accessible to an unpredictable and potentially very large number of clients. As a consequence, the process developer is confronted with the difficult question of resource provisioning. Determining the optimal configuration of the distributed engine that runs the process becomes sensitive both to the actual number of clients and to the kinds of processes to be executed. The main contribution of the paper is to show how resource provisioning for software business processes can be solved using autonomic computing techniques. The engine separates execution in two stages (navigation and dispatching) and uses a controller to allocate the node of a cluster of computers to each one of those stages as the workload changes. The controller can be configured with different policies that define how to reconfigure the system. To prove the feasibility of the concept, we have implemented the autonomic controller and evaluated its performance with an extensive set of experiments.}, keywords = {autonomic computing, distributed business process execution engines, service oriented architectures, Web service composition}, doi = {10.1016/j.infsof.2006.08.010}, author = {Cesare Pautasso and Thomas Heinis and Gustavo Alonso} } @conference {93, title = {Programming for dependability in a service-based grid}, booktitle = {3rd IEEE/ACM International Symposium on Cluster Computing and the Grid, 2003 (CCGrid 2003)}, year = {2003}, month = {May}, pages = {164 - 171}, publisher = {IEEE}, organization = {IEEE}, address = {Tokyo, Japan}, abstract = {Service-based Grid infrastructures emphasize service composition rather than sharing of low level resources. The idea is to build Grid applications out of computational services provided by the different sites of the Grid. Recent developments in the area of Web services have strengthened this idea by standardizing procedures like service description, publication and invocation. What is still missing is the infrastructure necessary to support the complete life cycle of applications running on service based Grids, i.e., suitable programming paradigms, execution infrastructure, and the ability to monitor and control such computations. Moreover, once computations are made of composable services, dependability becomes a key issue that needs to be addressed by the infrastructure as it cannot be addressed separately by each individual service. To address these concerns, we have developed the BioOpera Grid computing platform. BioOpera is a process support system for dependable cluster computing that has been extended with additional functionality to provide adequate support for service-based Grids. In this paper we describe how BioOpera can be used to develop, execute, and administer highly dependable computations over service-based Grids.}, keywords = {BioOpera, distributed business process execution engines, grid computing, Web services}, isbn = {0-7695-1919-9}, doi = {10.1109/CCGRID.2003.1199365}, url = {http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=1199365}, author = {Win Bausch and Cesare Pautasso and Gustavo Alonso} }